


Rapacity

by SympatriCuckoo



Category: Undertale (Video Game)
Genre: Angst, Incest, M/M, Non-Consensual Somnophilia, Sibling Arguments, Somnophilia, Unconscious Sex, bullshit soul magic, i guess we'll all find out together, i'm not entirely sure what i'm doing with this, only that i'm doing something
Language: English
Status: In-Progress
Published: 2016-01-13
Updated: 2016-06-12
Packaged: 2018-05-13 17:27:07
Rating: Mature
Warnings: Rape/Non-Con
Chapters: 2
Words: 1,931
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5710882
Author URL: https://archiveofourown.org/users/SympatriCuckoo/pseuds/SympatriCuckoo
Summary: <blockquote class="userstuff">
              <p>"Papyrus is sleeping peacefully in his bed, drooling lightly onto his shoulder. </p><p>Sans stands at the foot of the bed, wondering at his own depravity. He'd like to blame it on the resets, at the pure hell he's been put through watching everyone he knows and loves die over and over and he can't stop it can't do anything, but he was always a realist, unable to maintain the beneficial lies (that false veneer of hopes and dreams) that makes life worth living (that makes himself more bearable). "</p><p>Edited grammar</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> This wasn't going to be my first post on ao3, but this is what happens when I'm boozed up, apparently; though I figure someone might enjoy my sin of dubious quality, hence the post. I'm afraid I might've butchered Sans' personality here, so feedback on that part would be helpful for future (possibly smutty) purposes.
> 
> I guess an important thing to keep in mind is that, in one of the previous resets, Sans initiated a sexual relationship with Papyrus. It wasn't forced, but it lead to some serious consequences over which Sans feels awful. 
> 
> Bone appetit, fellow sinners!<3

Papyrus is sleeping peacefully in his bed, drooling lightly onto his shoulder.

 

Sans stands at the foot of the bed, wondering at his own depravity. He'd like to blame it on the resets, at the pure hell he's been put through watching everyone he knows and loves _die_ _over and over and he can't stop it can't do anything_ , but he was always a realist, unable to maintain the beneficial lies ( _that false veneer of hopes and dreams_ ) that makes life worth living ( _that makes himself more bearable_ ).

 

His brother is so sweet, almost unbearably so, and always was; and Papyrus is so innocent in all the ways that really mattered. From the moment Sans first held him, he was amazed at Papyrus' fragile innocence. And for all that the semblance of fragility had left as Pap had aged into adulthood, it always reappears when he is asleep.

 

Just the semblance, mind. Sans knows quite well how fragile that innocence is-from the other time-lines. _Intimately_.

 

Sans'd been the one to break it, frustrated at the dashed hopes that flavored his brother's red scarf. At the taking and ruining of that innocence the human had no right to. ( _That Sans had no right to either, but didn't that just make tasting the forbidden fruit sweeter._ )

 

Carefully, Sans crawled on the bed and straddled his brother, eyes warily searching for signs of waking ( _Not that being awake would dissuade him, necessarily. In other resets, he'd enjoyed his brother to the fullest in all states_ ). But not in this one. In this one he'd be strong. He wouldn't drag his cool, precious brother down with him. ( _And Pap had such a long fall, too._ )

 

Balancing himself on one hand, Sans leans over to nuzzle his face against Papyrus' breath hitching as he drags his other hand down his own body, from his throat to his clavicle. He spends a minute there, lightly rubbing-imagining that it's Papyrus, looking at him questioningly, curiously, as his fingers rub on all the sensitive ( _vulnerable_ ) areas at the base of Sans' neck.

 

Pulling back to look down at Papyrus' sleeping face again, Sans lets his hoodie fall off his shoulders and pool low around his elbows. Other hand now free, he uses it to pull up his t-shirt, the hand caressing his clavicle moving down to trail along his sternum and across his ribs. His breath catches as he fingers the sensitive undersides of ribs, eyes hooded as he scratches a little against the cartilage.

 

He imagines ( _remembers_ ) performing like this for Papyrus, his brother's eyes alight with interest and heat. And Sans huffs out a quiet laugh as his fantasy ( _his memory of_ ) Papyrus fidgets with the need to do something but unsure what that something is.

 

Pressure builds up in Sans' pelvis as he continues to tease himself, shivering as he pushes at his xiphoid process. A particularly hard shove to the sensitive hardened cartilage, bordering on painful, has Sans biting his shirt. One hand still playing with his xiphoid, the other runs down his vertebrae, pausing here and there to stroke between them before reaching his coccyx and rubbing.

  
Sans exhales hard, teeth grinding into the fabric of his shirt, magic slowly staining the grey cotton blue as his tongue materializes from pleasure. He can feel his magic straining to produce his cock, but Sans fights against its materialization. For now, the bearable discomfort adds to his pleasure.

 

His eyes had never left his brother's face, but for a minute, he just stares unthinking, looking his fill as pleasure thrums through his body. Papyrus snuffles a little, shifting his head to a more comfortable position, and the moment ends as thoughts and fantasies ( _and regret_ ) rush back in.

 

It's a heady mixture: love and lust mixed with desperation and self-hate and all shot through with the possessive desire to claim for himself ( _to hold and tie his brother to him tightly. To take a part of that innocence for himself and to then take it apart_ ).

 

With trembling hands, Sans pushed the waistband of his shorts down to mid-thigh, leaving his pelvis and cock bared. Pushing back memories of previous resets, Sans focuses on the now (on stealing into Papyrus' room and masturbating on top of his clueless younger brother), roughly thumbing the head. It is just a little too painful, too dry to be comfortable, but Sans revels in it ( _self-recriminations mingling with bitten back moans_ ). Pre-cum rapidly beads from the slit, thumb rubbing it around the head before Sans sets to work in earnest.

 

Sans shifts up, hips jutting forward as a rests his cock against the swell of covers blanketing Papyrus' chest. He starts slowly thrusting back and forth, thumb rubbing along the shaft, for both stimulation and to hold himself steady as he frots against the comforter.

 

He wills his mind to quiet. He wants to take in all the details (the feeling of sweat running down his spine; the delicious juxtaposition of the coarse wool of the blanket and the silky ribbon hemming the top; Pap's breathing, deep and even, ghosting over his cock-head on every other thrust) to commit this fully to memory before burying this monstrous side of himself under as many locks and layers as he can ( _for this time-line, at least_ ).

 

With a hastily suppressed sob, Sans comes. Pleasure drowning out the guilt, he eagerly jacks his release onto his brother's sleeping face.

 

Later, Sans will worry over the state of the bed linens. Later, he will take a short-cut back to his own room. Later he'll castigate himself and try to make it up to Papyrus. But for now, he sits and watches as his magic is slowly absorbed into his brother's bones.

 

 


	2. Chapter 2

**Notes for the Chapter:**

> sfw 
> 
> Finally posting this here. Because I'm apparently committed.

Papyrus opens his eyes and immediately knows that something is off. A scan of his room shows that everything is exactly as he'd left it before going to sleep. There are no Styrofoam cups festooning his floor, no balloons filing his room, and he and his bed aren't covered in glitter.

 

Shrugging slightly, Papyrus summons his slippers and gets out of bed. The slippers go whizzing across the room and Papyrus ducks, wide-eyed. They ricochet of the wall and slam into his computer, dropping harmlessly onto the keyboard.

 

At once, Papyrus knows what's wrong.

 

There is something different about his magic today.

 

If there's one thing Papyrus knows, really, _really_ knows, it's his own magic. Being able to stop attacks from doing damage mid-cast, being able to change his stats at will, being able to cast magic that is complementary or opposite to his own: these all required him to have absolute control over his magic. And, in order to gain control of his magic, his first step had been to know it-to know its fluctuations, its frequency, wavelength, how to group patterns and probabilities into basic formations of himself. 

 

And while he knows that he probably should take the time to really examine his soul, or at the very least take it easy, he also doesn't feel, well, _bad_. Aside from what he now recognizes as the hum of restless energy in his bones, he feels refreshed and happy, as though he'd had a particularly wonderful dream.

 

Papyrus dresses and makes his way downstairs to start breakfast. To his surprise, Sans is already awake, sitting on the couch and watching television, although Sans' focus switches to Papyrus almost immediately.

 

“GOOD MORNING, SANS! YOU'RE UP EARLY TODAY!”

 

Papyrus makes his way down the steps, like he always does, footsteps even and posture relaxed. Still, something must show on his face because Sans' lazy expression narrows to a laser focus.

 

“'morning. What's up?”

 

Papyrus would be surprised and puzzled if he wasn't so used to how perceptive Sans could be; many a retaliatory prank had been foiled because of how well Sans could read him. But as it is, Papyrus shrugs it off with a bright smile and sits on the couch.

 

“NOTHING MUCH. MY MAGIC JUST FEELS A LITTLE UNSETTLED.”

 

Sans mutes the television and looks concerned. “That's unusual for you,” he says slowly, a worried cast to his smile.

 

“IT IS,” Papyrus agrees, because it is unusual. His magic has always been quite steady, had become even moreso once he had begun to actively control it. “BUT, IT FEELS OKAY. I DON'T FEEL ILL,” he hurries to add, because Sans is beginning to look disturbed. 

 

“Papyrus.” There's a protective, concerned tone to his name that reminds Papyrus of all the times he'd done something reckless as a child. It's a tone that urges Papyrus to be more careful, be more aware of his own limitations. It's irritating, especially since Sans never heeds his own advice. 

 

“DON'T WORRY, SANS. YOU KNOW I TAKE VERY GOOD CARE OF MY SOUL AND MAGIC.” And at the reminder, Sans nods because Papyrus is scrupulously careful about his magic to make sure that he has it under control at all time s, has meditated, scrutinized it daily, ever since he had become strong enough to hurt Sans.

 

And if Sans still looks reluctant, Papyrus dismisses it. His older brother could be such a worrywart at times! After all, Papyrus isn't a child anymore; he doesn't need protection. Of all monsters, Sans is the most vulnerable with his 1HP.

 

~*~

 

Breakfast is calm.

 

Papyrus reheats some leftover spaghetti while Sans munches on ketchup and toast. When they're both finally seated at the table, they chat about their plans around bites of food. Papyrus says he's meeting Undyne for more lessons and Sans hums, a little preoccupied.

 

As Papyrus watches, Sans takes a bite of his toast, then hurriedly reaches for the ketchup and chugs.

 

“ARE YOU ALRIGHT?” Papyrus asks, because normally there would be no way Sans would make that mistake.

 

A look of satisfaction on his face, Sans wipes his mouth on his wrist. Papyrus grimaces and hands him a napkin.

 

“Just thinking,” Sans says. He pushes the napkin away, then fidgets with the bottle. “Maybe you should ask Undyne to check your magic when you're there.”

 

Papyrus puts his fork down. “SANS! I SAID I WOULD TAKE CARE OF IT!”

 

“Well, you never _actually_ said that.”

 

“SANS!” Papyrus can feel himself frowning. It's galling to be treated like you're still a child.

 

Sans holds his hands up in surrender. “I just worry about you! Sometimes you're too optimistic.”  
  


Papyrus mentally counts to ten, slowly; tries to make eye contact, but Sans is staring at his ketchup. “SANS, I CAN TAKE OF MYSELF.”

 

Papyrus waits for Sans to respond, but Sans continues to stare at his ketchup bottle, and eventually Papyrus goes back to eating.

 

It's disappointing that Sans apparently still sees him as a little brother, a little kid, to protect. While a part of him would love nothing more than to argue the point, he knows that, if Sans really thought that, there's nothing that could be done right then and there to change Sans' mind. Besides, starting a fight first thing in the morning at the kitchen table would be rather immature. And it would be even worse to give vent to his anger with his magic still in such a volatile state.

 

They finish the meal in silence. Papyrus puts their plates in the sink to soak, then walks briskly to the front door, passing Sans and pausing only to feed the rock.

 

“Hey, uh, have a safe trip.”

 

Hand on the knob, Papyrus stops and nods, really more of a short jerk up and down of his head. “THANK YOU. TAKE CARE, SANS.”

 

 


End file.
